While rats have been regarded as an important animal model system that can recapitulate the pathology of various human diseases, including, but not limited to, cardiovascular (e.g., hypertension), metabolic (e.g., obesity, diabetes), neurological (e.g., pain pathologies), and a variety of cancers, the use of rats in modeling human diseases has been limited as compared to mice, due in part to unavailability of germline-transmittable pluripotent rat cells, which can sustain their pluripotency following a series of genetic modifications in vitro, e.g., one or more serial electroporations, and due in part to lack of efficient targeting technologies that allow introduction or deletion of large genomic DNA sequences, or replacement of large endogenous genomic DNA sequences with exogenous nucleic acid sequences in pluripotent rat cells.
There is a need in the art for compositions and methods that allow precise targeted changes in the genome of an organism, which can open or expand current areas of target discovery and validate therapeutic agents more quickly and easily.